The present invention relates to a pump system, and more particularly to a pump system which may be interchangeably utilized for either a clockwise or counterclockwise propeller shaft rotation.
Multi-engine propeller aircraft utilize pump systems which are driven by a propeller system gearbox. Typically, a pump system is mounted to a bulkhead within an engine nacelle of each engine to locate the main pump in proximity to the propeller system and associated gearbox. On multi-engine propeller aircraft, the propeller on adjacent engines typically rotates in opposite direction to counteract torque. That is, the propeller system of engine one rotates clockwise, the propeller system of engine two rotates counterclockwise, the propeller system of engine three rotates clockwise, and the propeller system of engine four rotates counterclockwise. Although an advantage from a propulsion perspective, such alternating rotations complicate pump installations as the engine gearboxes are also rotating in opposite directions. The associated pump drive systems must accommodate these specific rotations.
Conventional pump systems include a male drive shaft that extends from the pump system. Such conventional pump systems are designed to be driven from either end by switching the shaft. That is, a mounting structure is located on one end of the pump and a relatively significant blanking plate is bolted to the unused end to close the unused end of the pump against full pump pressure. This permits any single pump to accommodate either a clockwise or counterclockwise driven propeller system.
Disadvantageously, such conventional pump systems require that a clockwise mounting plate, a counterclockwise mounting plate and blanking plate be carried on the pump system at all times which increases system weight. The male drive shaft must also be removed and replaced to the opposite side to change the pump system to an opposite propeller rotation position. Such changeover requires disassembly of the pump at a significant depot level maintenance facilities which may increase aircraft downtime. The changeover to assure proper drive direction is a relatively complicated procedure which may further complicates maintenance time and expense.
Accordingly, it is desirable to provide a lightweight engine driven pump system which accommodates either a clockwise or counterclockwise propeller shaft rotation.